Time flies like a white horse, and it is the day of school in a flash.

Xiao Ran Laboratory.

"Senior Brother Kong, you will carry out the synthesis of compound No. 1." Xiao Ran stood in front of the experimental table and said to Senior Brother Kong, who was preparing the experimental materials.

Senior Brother Kong nodded, Xiao Ran handed over the test tube in his hand when he saw this, and ordered: "First dissolve 5g of 3-chlorothiophene in dry tetrahydrofuran, the dose of tetrahydrofuran is 30 ml, and stir thoroughly, then cool the mixture to -78 °C, and add 5.56 ml of n-BuLi reagent dropwise."

"Xiaoxi, you can synthesize the No. 2 compound, no problem, right?"

"No problem!"

"Well, you need to add 1.14 grams of diethyl and 70 grams of triphenyl phosphorpalladium to 20 ml of toluene and 4 ml of DMF to the mixed solvent, then heat the mixture to reflux and stir continuously."

"Qian Wenbin, who is responsible for the synthesis of compound No. 3, first added 19 ml of sodium hydroxide solution to the test tube"

"Lin Xiaoxiao, you are responsible for recording the experimental data, remember that every step must be recorded in detail, down to what model of reagent is used, where it is taken from the laboratory, and which company it is purchased from, understand?"

"Understood, Director Xiao!"

After the run-in of the last semester, everyone's tacit understanding has improved a lot this semester.

Finally, there is a little prototype of a scientific research team, but there is still a long way to go from qualified scientific research dogs, but fortunately, Xiao Ran didn't expect them to play much of a role in this project research, and they should have accumulated experience.

At present, the research progress of the entire project has reached about 90%, of which Xiao Ran has completed more than 80% of the work by himself.

Of course, only Xiao Ran, who has mastered the entire organic solar cell technology, is clear to see how far this research progress has reached.

As for the rest of the lab, they don't know where they are in their research, or even if they are going in the wrong direction.

Of course, it's no wonder that they, in fact, this is the daily life of a research dog.

Take this organic solar cell as an example, if you want to develop a new type of organic solar cell with an energy conversion rate of about 20.26%~21%, the most critical point is the ternary copolymer in this technology.

In order to obtain this terpolymer, two new types of Cl-region isomeric units, TTO and TTI, need to be designed and synthesized, and then incorporated into the PM6 backbone as the third unit by random copolymerization to form ternary copolymers.

The main principle is that the introduction of TTO and TTI will reduce the HOMO level of the terpolymer and increase the open-circuit voltage. (HOMO: Highest Occupied Molecular Orbital, which means the highest occupied molecular orbital, which is the highest energy orbital of the electron that has been occupied in the molecule, representing the electronic state that is most likely to participate in the reaction of the molecule)

The TTO units with multiple non-covalent interactions, corrected electrostatic potential, and fewer isomeric structures lead to better molecular coplanarity, stronger crystallinity, and more obvious aggregation behavior.

These properties favor exciton dissociation, charge transfer, and charge collection.

For this reason, the difficulty of this project is how to obtain this terpolymer.

Take the heterogeneous unit TTO as an example, if you want to synthesize this new type of Cl-region isomeric unit, you need compound No. 1, which is the experiment that Kong Jiyuan is doing now.

Compound No. 1 was stirred at -50 °C for 2 h and then cooled again to -78 °C, under these conditions, 14.53 ml of Me3SnCl was added at a time and stirred for another 1 h, followed by recovery of the solution to room temperature and stirring overnight.

Finally, the resulting mixture was poured into water and extracted with DCM to obtain a light yellow oily substance extract, which was named compound No. 4.

Then, compound No. 4 was synthesized and extracted by adding other chemical substances, and finally a new type of Cl-region isomeric unit TTO was obtained step by step through four interlocking experiments. In the same way, compound No. 2 and compound No. 3 are synthesized into compound No. 5, and then after repeated extraction, catalyst addition, etc., finally TTI is obtained.

This is a very complex and tedious experiment.

If you don't know the answer, then you can only use trial and error, that is, one test at a time.

How do I get compound No. 1? How many grams of 3-chlorothiophene, four grams? Five grams? Or six grams?

How many milliliters of THF is appropriate? How many degrees should the dissolved solution be cooled after stirring? How many milliliters of n-BuLi reagent to add?

Of course, these can be derived from the data, and then the optimal ratio can be calculated through the formula, but how does this data come from?

It still needs a lot of experimental data support, and when these parameters are more than a certain number, the trial-and-error method can definitely make the scientific research dog in the laboratory painful, and hundreds of experiments are guaranteed, thousands of times are the norm, and the upper limit is unknown.

Just thinking about it makes people's scalps tingle.

But this is obviously for others, for Xiao Ran, his advantage is that he is familiar with all the experimental procedures, the data, and knows how much dose of tetrahydrofuran should be used, how many degrees it needs to be cooled to finally obtain compound No. 1, and so on.

This is also the courage of only five people in his laboratory to dare to tackle the new organic solar cell project.

He could even develop a new type of organic solar cell in one go without making a mistake, which is a bit shocking.

Others have tried thousands of times and can't find the right ratio to achieve the best performance, you can succeed the first time, and anyone who sees it will feel that there is a problem at first.

So if you don't want to be suspected, it's better to honestly do a few more sets of controlled experiments, with enough fault tolerance, control data, your final answer can be convincing.

With the experiments in the first two months, Xiao Ran felt that the time was almost ripe, so he simply didn't install it, and directly opened the low-temperature freezer where the reagents were stored, and took out the No. 8 compound and the No. 10 compound from it.

This is a batch of No. 8 and No. 10 compound reagents that he made three days ago, a total of 20 reagents, two of which are reagents of the correct ratio, and Xiao Ran marked them with the numbers 8-21 and 10-12.

Each took out five No. 8 and No. 10 compounds, mixed 8-21 and 10-12 into them, and then walked to his own experimental table, bowed his head and began the experiment.

With the experience of Carl Barry Sharpens, Xiao Ran's experiments are simply pleasing to the eye, especially compared to Kong Jiyuan next to him, it is simply a dimensionality reduction blow.

It didn't take long for Xiao Ran to synthesize five new Cl-region heterogeneous units, TTO and TTI.

After marking them as usual, Xiao Ran handed over the ten samples to Lin Xiaoxiao and instructed: "Xiaoxiao, help me take these ten samples for FTIR spectroscopy analysis." ”

"Okay!" Lin Xiaoxiao took the sample with a smile, walked quickly to the only Fourier transform infrared spectrometer in the laboratory, and then operated the instrument, putting each sample into the spectrometer one by one for testing.

Just as Lin Xiaoxiao was busy operating the Fourier transform infrared spectrometer, there was a gentle knock on the door of the laboratory, and then a familiar voice came: "Xiao Ran, are you inside?" ”

Xiao Ran looked up and saw Director Tian standing at the door with a smile on his face, still holding an envelope in his hand, looking mysterious.

"Teacher Tian, why are you here?" Xiao Ran greeted him with some surprise, "Is there any new instruction?" ”

Director Tian waved his hand and signaled Xiao Ran not to be so formal: "There are no instructions, but there are a lot of concerns." How's it going, is your project going well? ”

Xiao Ran said: "It's going well, and I haven't encountered any problems in my research at present." ”

Director Tian was amused by Xiao Ran, because of Xiao Ran, he has not paid much attention to this organic solar cell project during this time, and naturally knows how popular this project is, and many top universities at home and abroad have participated in the competition.

A team of professors in chemical engineering from the University of California, America, is currently leading the way, and the energy conversion rate of organic solar cells has reached 16.2%.

The competition in scientific research is extremely cruel, and it has always been a winner-takes-all, whether it is honor, resources or attention, it will only belong to the first place.

In the organic solar cell project, regardless of the factors of materials and cost, the energy conversion rate is the only factor to measure the value of the project.

Before the new record is broken, the research results below 16.2% are meaningless, of course, it may not be rigorous to say so, if the research is novel and innovative enough, it can still be published in some secondary journals, as for the top journal, that is not a thought.

In fact, since the University of California's research results came out, many colleges and universities have chosen to withdraw from the competition, which is a wise choice.

In the field of scientific research, success often leads to more success. Once a team or researcher achieves breakthrough results, they are more likely to receive funding for follow-up projects, which in turn makes it easier to attract high-quality resources and talents, thereby further consolidating their leading position.

This Matthew effect makes the competition even more brutal, because those teams or researchers who have already achieved success often have a greater competitive advantage, while those who fail to achieve significant results may be trapped in a vicious cycle that is difficult to turn over.

In this case, the research team that can continue to compete with the University of California has either reached an energy conversion rate of 16.2% and is only hidden, or has already launched a charge for higher numbers.

As far as Director Tian knows, the research team of Wu Maocai, vice president of their school's Institute of Chemistry, has studied about 17%, while the research teams of other universities have not yet come out, but they must not be lower than this number.

Compared with these top teams, Xiao Ran, a team of only five or six people, with the highest degree being only a graduate student team who has not yet obtained a degree certificate, seems so shabby.

It is no less than a five-year-old child and several strong men with a height of 1.9 meters in the ring, and the result can be imagined.

Lao Tian only thought that he was young and thin-skinned, and he was embarrassed to say his situation, so he could only slap his swollen face and become fat, and hold on.

He didn't intend to expose him, in his opinion, this was also a good thing for Xiao Ran, so that he could understand that scientific research was not as simple as he imagined, so it was better to take care of it as soon as possible and return to the field of mathematics.

Retracting his thoughts, Lao Tian smiled: "You kid, you can say nice things, forget it, I don't bother to care about you, by the way, I have one more thing to tell you this time." ”

As he spoke, Director Tian raised the envelope in his hand: "This is an invitation letter from Cambridge University, inviting you to give a lecture." ”

Xiao Ran was stunned when he heard this: "Cambridge University? Giving a lecture? ”

Director Tian said with a smile, "You have forgotten that half a year ago, at the International Mathematical Union, Professor Robert of Cambridge University invited you to give a lecture in their school. Isn't this coming! ”

Xiao Ran couldn't laugh or cry: "I've almost forgotten this, how can they still remember?" ”

Director Tian laughed: "This shows that your talent has been recognized, besides, the 500,000 pounds can't be spent in vain, right?" ”

After joking about Xiao Ran, he paused, and said earnestly: "This is also a rare opportunity, go out and communicate more with your international counterparts, your main business is mathematics after all!" ”

Hearing the conversation between Director Tian and Xiao Ran, Kong Jiyuan's heart tightened. Of course, he knew how honorable it was for Xiao Ran to go to Cambridge to give a lecture, but he knew even more that his research was now at a critical juncture.

If Xiao Ran left at this time, wouldn't their efforts in the past few months be in vain?

Kong Jiyuan couldn't help but interject: "Teacher, if Senior Brother Xiao leaves at this time, then our experiment"

When Director Tian heard this, his brows furrowed, and he looked at Kong Jiyuan: "What's wrong with your experiment?" Could it be that without Xiao Ran, you can't do experiments? ”

Kong Jiyuan was a little embarrassed by Director Tian's question, but he still stubbornly said: "Director Tian, you may not know very well, the research progress of our project has always been controlled by Senior Brother Xiao, if he leaves, we really don't know what to do." ”

"So what's the progress of your research now?" Director Tian's tone was filled with a hint of dissatisfaction.

Kong Jiyuan hesitated for a moment, but still said truthfully: "At present, the highest energy conversion rate has only reached 9.6%. ”

“9.6%？” Director Tian's voice raised an octave, "You have been studying for so long, and you have come up with a 9.6%?" Do you know that Vice Dean Wu Maocai's team has studied about 17%! And their team includes academicians, Changjiang scholars, professors, and a large group of graduate and doctoral students! What about you? Just a few of you, what do you compare to others? ”

Kong Jiyuan was speechless by Director Tian, of course he knew that their team and Vice Dean Wu Maocai's team could not be compared, but because they couldn't compare, they couldn't compare?

At the beginning, our country was not as good as America in all aspects, didn't we still dare to compete with Lao Mei?

However, he could only hold these words in his heart and did not dare to say them.

I had to say sullenly: "Teacher, you may have some misunderstandings about our project, our goal is not to surpass Vice Dean Wu's team or the research team of other universities. We're just doing our own research. ”

"Your own research?" Director Tian laughed angrily, "Then what's the point of your research?" Is it to study an energy conversion rate of 9.6%? ”

Belch.

Kong Jiyuan was completely speechless.

At this time, Xiao Ran suddenly asked, "Teacher, when is the lecture?" ”

"Next week."

Next week, Xiao Ran pondered for a moment: "Enough!" Don't worry, teacher, I'll be there next week at the Cambridge lecture. ”

"Senior Brother Xiao" Kong Jiyuan wanted to say something more, but he was glared at by Lao Tian, he screamed a few times, and finally had to hold back the words back into his stomach with grievances.

"That's right!" Retracting his gaze, Lao Tian patted Xiao Ran's shoulder with relief: "I was not optimistic about your project from the beginning, so it's better to give up as soon as possible and put your focus back on mathematical research!" ”

As soon as the words fell, I heard Xiao Ran say slowly: "Teacher, when did I say that I was going to give up this project?" ”

Well?

Lao Tian was stunned, what do you mean by this?

Before he could come back to his senses, he heard Lin Xiaoxiao suddenly shout in surprise: "Director Xiao! The characteristic peaks of TTO-21 and TTI-12 fluctuate significantly between 1500-1300 cm-1! ”

(End of chapter)